''I think the challenge has been that around the country, people perceive that we're doing alright,'' he said.

''Because if you look at our compliance with various outcomes the Ministry of Health is after, our operating workload, that type of thing, we're achieving what we're supposed to be doing, but it's come at a cost for the people who are providing the service.''

Mr Robertson describes the system as still fragile - and that includes its staff.

''There are people now that have had enough ... people are saying, 'you know my family in particular are saying it is time to leave, we can't put up with this anymore' ....

''Families are saying 'it's no good', so we've lost a lot of good people, often because of familial pressures are making a call to leave town,'' he said.

Critical challenges

Insight reports that Christchurch hospital is a building site these days as the board goes about inspecting, repairing or simply demolishing structures there.

Surgeons tip their hats now to the maintenance and engineering crews whose efforts meant operating theatres could function, sometimes in darkness and with intermittent water, on the night of 22 February.

Chief executive David Meates said all facilities and vital equipment are checked after every significant aftershock, certainly anything above a magnitude 5.0.

Buildings and staff are the two areas that pose the critical challenges facing the system.

Chairman Bruce Matheson said 700 people have been moved out of damaged buildings to other premises.

John McKie, the clinical head of the orthopaedic service, says Christchurch hospital now has more than 100 fewer beds than it did a year ago.

Operating theatres at Ashburton hospital also recently had to be closed because of the risk posed by unreinforced masonry.

The DHB estimates the overall price of the damage so far is more than $100 million.